The death toll from this week's mudslides in northern China continues to rise with at least 700 people confirmed killed and 1,000 still missing.  Some environmentalists and survivors say unrestricted logging on surrounding mountains contributed to the mudslides. 

Thousands of soldiers, emergency workers, and survivors are racing to find people buried under mud and rubble in Gansu province's Zhouqu county before more rain storms hit as expected this week.

But hopes are fading of finding anyone alive from mudslides Sunday that ripped apart buildings and homes and covered entire villages.

Heavy rains early Sunday caused flooding and mudslides that blocked part of a nearby river, forming a lake that still threatens to burst.

Soldiers are using explosives and excavators to try to quickly drain the lake.  But there is concern further rains could cause it to flood, putting people at risk and spreading disease from decomposing bodies.

China's Vice Minister of Water Resources, Jiao Yong, sought to reassure the public in a live briefing broadcast Wednesday saying there are contingency plans for handling the situation.

He says first they will strengthen early warnings and forecasts for weather, water conditions, and possible floods.  Second, he says if there are floods, they will initiate a plan for emergency evacuations from dangerous areas.

Already, at least 45,000 people have been relocated from the remote valley where the mudslides took place.

Food, water, and tents have been rushed in, and workers have sprayed disinfectant to prevent the spread of disease.  Officials say supplies are adequate for current needs.

Some survivors and activists partly blame deforestation and poor flood control plans for the severity of the disaster.

However, Guan Fengjun, deputy director general of the Ministry of Land and Resources rejected that view, saying they have so far determined it to be a disaster caused by nature.

He says their experts on the ground will continue to follow the possible impact of human activities, and that they will have further studies which will be included in their final report.

China's official Xinhua news agency said roads were repaired Wednesday and heavy digging equipment was brought in to accelerate clean-up operations.

Xinhua said it was the deadliest mudslide to hit China in decades.